Surface plasmon dispersion analysis in the metal-oxide-metal tunnel diode

Abstract

Three peaks corresponding to the ultraviolet, visible, and near infrared were recently observed in the light emission spectra of a metal-oxide-metal (MOM) tunnel diode. This was the first time UV emission was reported at room temperature with a MOM diode, and it was associated with the radiative surface plasmon. Simple dielectric theory predicts the location of the UV peak as well as the others, but is unable to give a complete description of the spectral output. To gain a clearer understanding of the spectral emission, a more comprehensive detailed model of surface plasmon dispersion in the MOM system is presented. The model is very general and includes the effects that different oxides, metals, and their thicknesses have on the dispersion curves. When applied to simpler systems, the model agrees well with the theoretical work of others. Also, associated with the cathode-oxide interface is a nonradiative mode that is found to play a major role in the transition from the visible to UV peaks in the diode's spectra.